What is the perfect backpack for me?! Help please!?

OK, well I'm going to the 8th grade, and i want to get the perfect bag for me, since the 6th grade and 7th i ALWAYS been a TranSport fan. But what i have noticed in the 7th grade people are carrying totes, or book bags that are not full. My backpack is SUPER full, and its big too. and for a small petite girl like me, it just looks BAD. I try to clean out stuff and everything but everything in my bag is what i really need. and i want my 8th grade year to be the best it can be. I don't want to be carrying something heavy on my back anymore! And i think whats the problem is that my dad likes to pack me a really big lunch(since i cannot eat at school cafeteria, because i will pay to much $) in a lunch box, and if i get a tote bag, it will just look BIG. I'm in AVID and we are suppose to carry a 3 inch binder. but i carry a 1 inch binder. I'm thinking of just getting one of those regular backpacks like this from TranSport:http://www.tillys.com/tillys/variants.aspx?prod=144319765&ctlg=020_Girls&cid=1094&source=1&size= . But, if i carry the lunch, and all the necessity it might not even fit! It will just look SUPER BIG.Because the book bag is really small. I really want to carry a tote super badly. But, i cant seem to find a tote that can fit: a 1 or 2 inch binder, and just a little bit of room to fit my lunch.AND, still wont look big on me. I would like it to be over my shoulder BUT also on my shoulder here is a example:http://store.delias.com/item.do?itemID=52795&categoryID=416&sizeFilter=&colorFilter=&brandFilter= . Sorry for the long paragraph. i would SUPER DUPER appreciate it if you helped me found a perfect backpack for me. And a little help to with stuff i REALLY need in my bag. THANKS! :)